DRUGS USED FOR PAIN:

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Oral Morphine is the drug of choice for severe cancer pain - WHO

ACTION:

ACTION Activating opioid receptors in the midbrain & turning on the Descending inhibitory system Activating opiod receptors on the second order pain transmission cells to prevent the Ascending transmission of pain signals Activating opioid receptors at the central terminals of C fibers in the spinal cord Activating opioid receptors in the periphary to inhibit the activation of nociceptors & to inhibit cells that may release inflmmatoy mediators

Preparations of Oral Morphine Tablets (MST):

How to use:

How to use Start with 5 - 10mg i/r MST Always use q4h with double dose at bed time Additional doses can be given p.r.n. for breakthrough pain If pain relief is not satisfactory, increase by approximately 50% of previous dose Oral Morphine

Breakthrough dosing :

Breakthrough dosing When flares of pain last for more than few minutes, extra doses of analgesics may be helpful For each breakthrough dose, offer 5% to 15% of the 24-hour dose A breakthrough dose can be offered once Cmax has been reached

How to use:

How to use There is no maximum dose of morphine; the dose can be increased depending on the severity of pain “Pain is the physiological antagonist to the central side effects of morphine.” Oral Morphine

How to use:

How to use Always prescribe a laxative (stimulant +/- softener) prophylactically “The hand that prescribes the Morphine should also writes laxatives” Prescribe an anti-emetic prophylactically for the first few days , especially in patients who are already vomiting Oral Morphine

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Misunderstandings about morphine:

Misunderstandings about morphine ‘Morphine is dangerous because it depresses respiration’ Double dose at bed time does’nt cause RD Large therapeutic window Drowsiness and delirium prevents from taking further dose Tolerance to respiratory depression develops in course of time Oral Morphine

Misunderstandings about morphine (contd):

Misunderstandings about morphine (contd) ‘Morphine is addictive’ Several studies have concluded that risk of addiction is far less than 1% Two studies with more than 500 patients who received Heroin for pain relief found that no patient could be documented as having become addicted Twycross, 1974; Twycross, Wald, 1976 Prospective study of 11,882 hospitalised medical patients only 4 patients could be documented as having become addicted as a result of receiving opioid analgesics Porter, Jick, 1980 Oral Morphine

Other Indications:

Conclusions:

Conclusions Oral morphine is the drug of choice for severe cancer pain management It is always safe in “safe hands” Respiratory depression, addiction and tolerance are not problems with oral morphine Oral Morphine

Fentanyl:

Fentanyl Convenient 25 times expensive Not useful for break through pain Latency of action Acts up to 24 hrs after removal of patch Titration not possible if the patient becomes drowsy Practically no role as first line It works better in cool climate

Paracetamol:

Paracetamol ADVANTAGES DRAWBACKS No Injurity to Gastric mucosa No nephrotoxicity No platelet dysfunction It can be taken by 2/3 rd of patients hypersensitive to aspirin/NSAIDS Safe up to 6-8 g/day Large doses 20mg/m 2 Large size tablets Frequency of administration 4-6 th hourly Hepatotoxicity